Pocketed spring cores or assemblies are commonly used in seating or bedding products. Such pocketed spring assemblies are commonly made of multiple strings or rows of individually pocketed springs. Adjacent strings of individually pocketed springs are joined together by gluing or otherwise attaching the fabric of the strings of springs to each other.
Pocketed coil springs are often referred to as a Marshall construction in which each coil spring is encased within its own fabric sack or pocket. The sack or pocket is typically defined between two plies of a fabric strip connected together at intervals along transverse lines of attachment spaced along the strip. The two-ply fabric strip is generally formed by folding a strip of double width fabric upon itself along a longitudinal centerline, leaving the overlapped plies along the unjoined opposite edges of the strip to be connected to each other along a longitudinal seam. After the springs are inserted between the plies, opposed plies are joined along transverse lines of attachment to close the pockets and separate adjacent springs.
A variety of techniques have evolved for the manufacture of pocketed springs, some contemplating the creation of the pockets within the fabric plies prior to insertion of the wire spring and others contemplating the insertion of compressed wire springs between the plies of the strip and the subsequent creation of the pockets by joining the two plies to each other along transverse lines of attachment between adjacent springs. In recent times, heat sensitive fabric and ultrasonic welding techniques have been utilized to join the fabric plies together along the seams or lines of attachment.
Pocketed spring assemblies are often inserted into a foam partial encasement or “bucket” as the term is used in the art. One or more upper layers of material may be located on top of the “bucket” to complete the foam encasement. The foam encasement may provide edge support and the appearance of a support border. If such foam encased pocketed spring assemblies are roll packed, the foam rails or any portion of the foam encasement may be damaged. If the roll is stored, transported and stored at the location of a bedding manufacturer for too long, the foam may not return to its original intended form when unrolled at the bedding manufacturer.
It is therefore an objective of this invention to provide a seating or bedding product which has a pocketed spring assembly interior and a perimeter of pocketed springs which may eliminate the need for a foam encasement.
Still another objective of this invention is to provide a seating or bedding product which has a pocketed spring assembly having an edge support made of pocketed springs with the appearance of a foam encasement.